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    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
    <script>
        const d = '123'
        function a(a) {
            console.log(a, 'a')  //fn(8)
            var a = 4
            function a() {
                console.log(8)
            }
            var a = function () { console.log('abc') }
            console.log(a) //fn()
            return a
        }
        var a
        console.log(a(3)) //fn()
        setInterval(()=>{},1)


        /**
         * GO:   a:undefined,fn(),fn(3)
         * AO:   a:undefined,undefined,undefined,3,fn(),4,fn
        */
    </script>
</body>

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